230 Royal Society : — 



times exceedingly small, requiring a J-inch objective to make them 

 out, when they can clearly be discerned to be a modified condition of 

 true hairs copiously supplied with nerves. The author names these 

 " tactile hairs,''' and points out their existence in all palpi used for 

 touching, and in other organs subservient to that function. These 

 tactile hairs are very large in the palpi and antennae of Dyticus mar- 

 ginalis. The barrel-like organs of the Lepidoptera are next investi- 

 gated, and are shown to have a nerve passing up them ; but whether 

 proceeding to the apex of the nipple-like papilla on them or not, 

 cannot be quite made out. They are pointed out as being nearly 

 allied to the organs on each of the palpi of the Earwig {Forficula 

 auricularia) . 



The author refers to the sacs found on the antennse of all insects, 

 which have been fully treated of in two papers read by him before the 

 Linnean Society, and published in their ' Transactions ;' and he lastly 

 examines the probable functions of all these organs, which must be 

 of sensation, probably special. 



Attention is also called to the value of bleaching the tissues by 

 chlorine in investigating the structure of insects, which process was 

 first used by the author and described by him in the papers above 

 mentioned. 



"On the Occurrence of Flint-implements, associated with the 

 Remains of Extinct Mammalia, in Undisturbed Beds of a late Geo- 

 logical Period." By Joseph Prestwich, Esq., F.R.S., F.G.S. &c. 



The author commences by noticing how comparatively rare are 

 the cases even of the alleged discovery of the remains of man or of 

 his works in the various superficial drifts, notwithstanding the ex- 

 tent to which these deposits are worked ; and of these few cases so 

 many have been disproved, that man's non-existence on the earth 

 until after the latest geological changes, and the extinction of the 

 Mammoth, Tichorhine Rhinoceros, and other great mammals, had 

 come to be considered almost in the light of an established fact. 

 Instances, however, have from time to time occurred to throw some 

 doubt on this view, as the well-known cases of the human bones 

 found by Dr. Schmerling in a cavern near Liege, — the remains of 

 man, instanced by M. Marcel de Serres and others in several caverns 

 in France, — the flint-implements in Kent's Cave, — and many more. 

 Some uncertainty, however, has always attached to cave-evidence, 

 from the circumstance that man has often inhabited such places at 

 a comparatively late period, and may have disturbed the original 

 cave-deposit ; or, after the period of his residence, the stalagmitic 

 floor may have been broken up by natural causes, and the remains 

 above and below it may have thus become mixed together, and 

 afterwards sealed up by a second floor of stalagmite. Such instances 

 of an imbedded broken stalagmitic floor are in fact known to occur ; 

 at the same time the author does not pretend to say that this will 

 explain all cases of intermixture in caves, but that it lessens the value 

 of the evidence from such sources. 



